Evolution of medical management of chronic rhinosinusitis.

Chronic rhinosinusitis (CRS) is a surprisingly common, poorly defined, and notoriously difficult-to-treat disease. It has a complex pathophysiology that often, but not always, involves nasal or paranasal sinus infection. Anatomic variations that predispose the sinuses to obstruction may play a role, but are unusual sole causes of chronic disease. Other possible causative factors include allergic or nonallergic inflammation, mucociliary dysfunction, aspirin intolerance (Samter's triad), immunodeficiency, and cystic fibrosis. Although a majority of patients achieve long-term relief from CRS after successful endoscopic sinus surgery, a significant proportion do not, and are likely to benefit from sustained postsurgical medical therapy. Medical therapy for CRS may include treatment with corticosteroids, antibiotics, antifungal agents, antihistamines, leukotriene modifiers, nasal decongestants, mucolytics, and nasal irrigations. The selection of appropriate medical therapy is based on endoscopic evaluation, sinus cultures, and symptoms. Computed tomography, the imaging standard for evaluation of the sinuses, provides information about the extent and distribution of mucosal disease beyond what is visible endoscopically. Because it fails to provide information on the origin of the mucosal changes, computed tomography provides limited information to guide medical therapy.